If we choose to live near convergent plate boundaries, we can build buildings that can resist earthquakes, and we can evacuate areas around volcanoes when they threaten to erupt. Yes, convergent boundaries are dangerous places to live, but with preparation and watchfulness, the danger can be lessened somewhat.
Nitrification, as stated above, is formally a two-step process; in the first step ammonia is oxidized to nitrite, and in the second step nitrite is oxidized to nitrate. Different microbes are responsible for each step in the marine environment.
Urea is decomposed by the enzyme urease or chemically hydrolyzed into ammonia and CO 2. In the ammonification step, ammonia is converted by ammonium-oxidizing bacteria into ammonium. In a next step, ammonium is converted by nitrifying bacteria into nitrate (nitrification).The nitrogen conversion rate depends on the conditions, present in the soil for nitrifying bacteria. Nitrates can be readily absorbed by the plant and do not need to undergo any further conversion, as is the case with urea and ammonium, before plant uptake. 2  No acidification of the soil if all the nitrogen is applied as nitrate-nitrogen.